Photo of the obverse would be helpful. It looks like a Caria, Kaunos. https://www.acsearch.info/search.ht...de=1&fr=1&it=1&es=1&ot=1¤cy=usd&order=0
I've been looking and the closest I can find is Ptolemaic Kings of Egypt, but nothing exact. What is the weight and size and what sources have you already reviewed?